The invention relates to dental treatment equipment and in particular to root canal dental instruments. Specifically, it relates to a self-contained root canal dental instrument that combines the operations of a root canal spreader, a root canal condenser, and a root canal filling material heater.
A need has existed for a long time for a way to reduce the time involved in filling a prepared root canal of a human tooth with the filling material. The time involved being used in the continual pick up of separate dental tools for spreading filling material, condensing the filling material, and the alternate heating and reheating of the filling material, during the spreading and condensing operations. This invention eliminates the problems and reduces the time, thus effectively reducing the cost of root canal work.
Gutta percha is the usual root canal filling material that is used for filling root canals. However, it is to be understood that this invention is usable on other root canal filling materials that are spread and condensed in the root canal and which are heated to improve the flow qualities of the root canal filling material.
The gutta percha material deforms when warmed and compressed. It becomes pliable at 25.degree. to 30.degree. Celsius, it becomes soft at 60.degree. Celsius, and it decomposes at 100.degree. Celsius. At such temperatures phase transition occurs allowing the gutta percha to flow into the many irregularities of the prepared root canal, thus allowing for a three-dimensional obturation and sealing to occur. Such a three-dimensional obturation and sealing is necessary for success in root canal therapy.
When the filling material, such as gutta percha, is softened, it is then compressed into the numerous aberrations of the root canal in order to effectively seal the root canal cavity. The compressing of the filling material in the prior art is performed by using root canal filling spreaders and filling condensers of a variety of sizes and with several handle designs (both long and short).
The filling spreaders and condensers of the prior art for root canal work are generally of stainless steel or chromium plated brass. The filling spreaders are smooth, flat ended and slightly tapered.
In use in the prior art, the root canal filling spreaders and condensers have to be heated over a flame, such as over the flame of a Bunsen burner, and then passed into the mouth of a dental patient and then into the prepared root canal where the filling material, such as gutta percha, has been placed. There is the constant danger of burning the patient about the mouth each time a heated dental tool is moved from the flame to inside the mouth. The present invention reduces the number of entries into the mouth that are necessary during a root canal filling, and also provides for inducing the heat for the tool after the tool is in the tooth at the root canal cavity.
Once a first portion of filling material is in the root canal, the filling spreaders are used to heat the filling material and then laterally condense or press the filling material into the root canal areas. Thereafter, a filling condenser is used to maintain the heat or reheat the filling material and to vertically condense the filling material into the root canal. This is a compacting type of operation. While the use of the filling condenser to vertically condense the filling material is often referred to as a plugging operation, the use of the filling spreader to laterally condense the material before the vertical condensing is also a part of the total plugging operation.
Additional bits or points of filling material are placed into the root canal cavity and then followed by the spreading and condensing operations described hereinbefore for the filling spreader and condenser root canal tools. These operations are continued until the required amount of filling material plugs and seals the root canal in accordance with dental art. However, it is to be noted that the repeated changes between filling spreader and filling condenser and the continual reheating of the dental tools increases the risk in the prior art of burning the patient as noted hereinbefore.
Regarding the gutta percha, or any similar filling material, the deformation under heat and stress allows compaction and condensation that leads to the lateral spreading to fill the voids in the root canal. As bits or points of filling material are placed into the root canal, as hereinbefore described, the heated spreader tool is forced between the bits or points of material after each such insertion which pushes the filling material to the apex of the root canal and, concurrently, laterally. The tool is pressed manually and also rotated side to side to achieve the spreading of the material.
It is to be noted that in this prior art the heated filling spreader, and also the heated filling condenser, must be transported quickly from the Bunsen burner into the mouth of the patient and into the tooth and the root canal and against the cold mass of filling material. The present invention reduces these numerous reheating and transport movements.
If hot enough, the filling material will not stick to the dental tools of the prior art. If the filling material retains the heat a cold filling condenser may be used to perform the plugging operation, however, this cold operation also tends to cool the filling material which then requires a reheating. However, general practice also shows that a small amount of the filling material often adheres to the dental tools. The present invention eliminates this condition as well as many of the repeated tool exchanges and reheating operations.
In the prior art some attempts have been made to provide for heating the tools while in the mouth. Problems encountered have been that the tips have been bulky and too wide, requiring some use of the old prior art tools mentioned hereinbefore. Also, the tips do not wedge lock into place and 360.degree. rotation has been encountered which reduces the effectiveness of the condensing operation.
The heat control has been unreliable, the system having as many as ten dial settings which required an assistant or required the dentist to stop the condensing operations to attempt to make a better heat selection or to interrupt the heat process.
In addition to the above problems, the filling material sticks to the surface of the socalled heat control tools, and the system has a cumbersome power box and control means.
In the medical/dental profession a self-contained cautery, used for cauterizing, is usable only for cauterizing and is not usable for root canal work, it is also bulky.
In the present invention, the self-contained root canal instrument is provided in a range of sizes of small plugger components for use from the area of the apex of the root canal up to and past the area of the mouth or entrance of the root canal from the interior of the tooth proper. The self-contained root canal instrument of the present invention in its range of sizes combines the functions of the prior art filling spreader tool, filling condenser tool, and the heating means. The end portion of the self-contained root canal instrument that is usable for the three operations of spreading, condensing, and heating is the plugging component. Thus, the present invention reduces not only the time and cost of filling root canals, but also reduces the armentarium necessary in the prior art.
The plugging component is provided in the aforementioned range of sizes and is provided for in a snap-in or chuck mounted method of attaching to a handle means and to a power source.
The plugging component is provided in several embodiments, each of which has a non-stick surface, such as Telfon, to prevent the filling material from adhering to the tool.
In the present invention the heating is controlled in order to stay within the range of that required for the filling material being used, so as not to under heat it and also not to char it or destroy it. In that regard, a contoured finger tip switch is conveniently located and provides for instant reheating as and if the filling material begins to cool below the workable deformation point.
Also, in the present invention the same instrument is used for softening the filling material by heat and for the compaction without withdrawing the instrument from the root canal of the patient's mouth.
In the present invention the range of sizes provides for a memory in the small sizes where it is necessary to have some flexibility in order to work around curves in the root canal. This is not possible in any of the prior art which has made attempts at a self-contained heating element.
It is, therefore, an object of this invention to provide a dental instrument for root canal work that is completely self-contained.
It is another object of this invention to provide a dental instrument for root canal work that combines the qualities and facility of a spreader and a condenser tool for lateral and vertical compacting of root canal filling material.
It is also an object of this invention to provide a dental instrument for root canal work that has a built-in means for heating the working portion of the tool.
It is a further object of this invention to provide a dental instrument for root canal work that has a range of sizes.
It is still another object of this invention to provide a dental instrument for root canal work that has a non-stick surface at the point of contact with root canal filling material.
Further objects and advantages of the invention will become more apparent in the light of the following description of the preferred embodiments.